try this: (is that what you wanted to achieve):
$('#myinput').change(function() {
if( $(this).val() == "dog") {
$('#cells').animate({'opacity':'0.2'},1000, function() {
$('#myinput').val('').focus();
$('#cells').css('opacity','1');
});
}
});
working fiddle here: http://jsfiddle.net/M4KgL/1/